Interconnect devices are used to provide electrical connection between two or more opposing arrays of contact areas for establishing at least one electrical circuit, where the respective arrays may be provided on a device, printed circuit board, Pin Grid Array (PGA), Land Grid Array (LGA), Ball Grid Array (BGA), etc. Interconnection techniques may include soldering, socketing, wire bonding, wire button contacts and plug-in connectors. In one interconnect technique using a Z-axis interconnect device, an array of Z-axis interconnect elements supported on a substrate provide electrical connection between stacked electrical components. The Z-axis interconnect device is capable of accommodating size constraints, such as related to the reduced physical size of many electrical devices. Additionally, the Z-axis interconnect devices may be non-permanently installed for accommodating the need to remove or replace components of an established electrical circuit(s).
Electrical conductivity may be provided by a Z-axis interconnect device having metal conductive contacts, each contact providing electrical connection between corresponding electrical contacts of the opposing arrays. Establishing reliable contact between the metal contacts and the metal contact areas of either of the opposing arrays may be unreliable due to height variations between electrical contacts of the opposing arrays, variations in thickness of a substrate supporting either of the opposing arrays of the conductive elements of the interconnect device, warping of a substrate of the either of the opposing arrays, etc.
In prior art electrical interconnect devices using conductive elastomeric conductive elements, such as disclosed in U.S. Pat. No. 6,056,557 and U.S. Pat. No. 6,790,057, an electrical interconnect device is provided with elastomeric conductive elements disposed in respective holes of the substrate, where the holes are arranged in a grid array. The elastomeric conductive elements are compressed between the opposing arrays, and due to the viscoelastic property of the conductive elements, the respective elastomeric conductive elements apply a mechanical force to electrical contacts of the opposing arrays for establishing reliable contact. However, the conductivity of the elastomeric elements is generated by the conductive particles contacting adjacent conductive particles under compression, resulting in a full conductive path. Additionally, the conductive elastomeric elements function optimally when in an isostress condition, which is not ideal for most interconnect applications.